Two stage compressive spring operated door check hinge

Abstract

Disclosed herein is a two stage compressive spring operated door check hinge. It has two springs of different length equipped along an outer tube to serve two stage restoring force. A unique design of collaborated function of the set billets and the corresponding containment holes enable the door to pause at a desired position. An adjustable nut is provided to adjust the elastic force of two springs such that the operation of the door can be carried out smoothly and silently without installing an awkward articulated door check arm.

What is claimed is:  
     
         1 . A two stage compressive spring operated door heck hinge comprising a base tube having a stationary wing plate at its side thereof for securing to the door body, a pad block of smaller diameter being formed at the upper end of said tube thereof, a center pin of even smaller diameter being extended upwardly form the center of said pad lock, a pair of symmetrically disposed guide tracks being formed at both sides of the lower end of said center pin; 
 an outer tube having a butterfly wing formed ay one side thereof for securing to a door frame, said outer tube having a diameter able to let it sleeve and enclose said base tube up to the upper end of said base tube, a pair of symmetrical spiral grooves being formed in its inner tube cavity;    a cylindrical slide block having several through holes formed at its center portion thereof being inserted into said center pin and said guide tracks of said base tube, a pair of symmetrical spiral rails being formed on its outer wall surface such that it being able to relatively slide with said outer tube by mating said spiral rails with said spiral grooves after it being conjunction to said outer tube;    an upper spacer block and a lower spacer block being provided on the top end of said cylindrical slide block, the inner parts of said spacer blocks being for equipping an inner spring, while the outer parts thereof being for equipping an outer spring; and    a fixing nut and an adjustable nut being screw engaged with said center pin by screw thread provided on said center pin;    with this structure, said outer tube is displaced stably following the door movement, the door can be opened easily and closed rapidly without any noise by means of said two springs' two stage restoring force.    
     
     
         2 . The door check hinge of  claim 1 , wherein a vertical hole is formed along the longitudinal direction through the body of said base tube outside of said pad block, a spring element having a set billet on its top end is contained in said vertical via hole, a spherical containment hole aimed at the corresponding position of said billet is formed on the bottom of tube body of said outer tube for permitting said set billet to enter so as to decide the stopping position of said outer tube and an open angle of the door.  
     
     
         3 . The door check hinge of  claim 2 , wherein said vertical via hole is plural.  
     
     
         4 . The door check hinge of  claim 1 , wherein said inner spring is longer than said outer spring.  
     
     
         5 . the door check hinge of  claim 1 , wherein the inner restoring force of said inner spring provides a pausing force for the door, while the restoring force of said outer spring provides a force rapidly closing the door.  
     
     
         6 . The door check hinge of  claim 1 , wherein said upper spacer block is formed of an inner tube and a pad block, wherein said inner spring is equipped in said inner tube, and said outer spring is enclosing over said inner tube.  
     
     
         7 . The door check hinge if  claim 1 , wherein said fixing nut and said adjustable nut screw engaged with said center pin are for adjusting the elastic force of said inner and outer springs.